The present invention relates to an optoelectronic apparatus and a method for producing the same. In particular, the present invention relates to an optoelectronic apparatus in which an optoelectronic device mounted on a resin package is sealed with an optical component, and a method for producing the same.
Examples of optoelectronic devices include a semiconductor laser device, which is a light emitting semiconductor device, and a light receiving semiconductor device. U.S. Pat. No. 5,748,658 discloses a semiconductor laser apparatus, an optical pick-up apparatus, an optical disk apparatus and the like, as an optoelectronic apparatus on which a semiconductor laser device and a light-receiving semiconductor device are mounted. FIGS. 7A and 7B show the structure thereof. FIGS. 7A and 7B are a schematic plan view and a schematic cross-sectional view of the structure, respectively. In FIG. 7A, an optical component 92 shown in FIG. 7B is omitted.
In the apparatus shown in FIGS. 7A and 7B, a semiconductor laser chip 70 mounted on a resin package 90 is sealed with an optical component 92. The resin package 90 is constituted by a frame member 91 made of an insulating material, a lead frame 73 including a chip mounting portion 74, and a protective plate 79. The semiconductor laser chip 70 is mounted on the chip mounting portion 74 via a silicon substrate 71 for heat sink. The optical component 92 sealing the resin package 90 on which the semiconductor laser chip 70 is mounted may be an optical flat plate or a holographic optical component. In FIGS. 7A and 7B, a heat sink 77 and a signal processing circuit 75 are also shown.
Japanese Laid-Open Patent Publication (Tokkai) Nos. 8-288594 and 7-183414 describe a semiconductor laser apparatus in which a semiconductor laser device is sealed by mounting and fixing a holographic optical component on a resin package including a frame member having steps with an ultraviolet curable adhesive.
The above-described conventional optoelectronic apparatus and the method for producing such an optoelectronic apparatus have the following problems.
With demands for large capacity and compactness of optical disk apparatuses, there is an increasing demand for a complex combination and compactness of optical components used in a semiconductor laser apparatus that is the core of an optical pick-up apparatus included in the optical disk apparatuses. The optical components are, for example, a diffraction grating, a prism, and a holographic element, and fixed onto a package on which a semiconductor laser apparatus is placed with an adhesive. Moreover, the package has a guide wall (denoted by 89 in FIGS. 7A and 7B) provided for rotation adjustment by contacting with the inner wall of a cylinder for the purpose of optical alignment of the semiconductor laser apparatus and the optical disk or the like. In recent years, with development in compactness of optoelectronic apparatuses, the distance of a space between the outer periphery of the optical component (denoted by 92 in FIGS. 7A and 7B) and the inner wall of the guide 89 has been reduced. This space serves as an adhesion portion to which an adhesive is supplied. Since this space is small, it is difficult to supply an adhesive to the adhesion portion (the space) after the optical component is mounted on the package.
In particular, in a method using a nozzle of a producing apparatus for mass production to supply an adhesive, it is difficult to insert the nozzle in the adhesion portion of a narrow space so that the nozzle cannot sufficiently be guided for appropriate fitting in the adhesion portion. Therefore, the adhesive cannot be applied to an intended portion of the optical component. As a result, the optical component cannot hermetically be fixed onto the package.
Moreover, unnecessary adhesive is applied to portions other than the adhesive portion such as the upper portion of the optical component and the periphery of the package, which leads to poor optical characteristics and poor mechanical dimension accuracy of the package. For example, when the adhesive is applied to the outer circumference of the guide wall of the package, problems may arise in alignment in some cases depending on other producing apparatuses, because alignment is performed based on the dimension of the outer circumference. In addition, a handler may not be used for holding the package.
Furthermore, since the adhesive is supplied to the overall adhesion portion of a narrow width in a wide range, the adhesive is stuck between the outer periphery of the optical component and the inner wall of the guide before the adhesive reaches the adhesion portion, so that air bubble can be contained. Thus, sufficient adhesion cannot be achieved.
In view of the above-mentioned conventional problems, it is an object of the present invention to provide an optoelectronic apparatus that can supply an adhesive easily and a method for producing the same.
An optoelectronic apparatus of the present invention includes an optoelectronic device, a mounting portion for the optoelectronic device to be mounted on, a frame member surrounding the periphery of the mounting portion, and an optical component. The optical component is placed on an optical component placement portion positioned in an inner peripheral portion on the side of the mounting portion of an upper surface of the frame member. The frame member includes a pair of first side walls opposed to each other in a portion of an outer peripheral portion positioned on an outer periphery side than the inner peripheral portion of the upper surface of the frame member, and a pair of second side walls opposed to each other in the portion of the outer peripheral portion other than the portion on which the pair of first side walls are provided. Each of the pair of second side walls has a recessed portion formed on an inner wall side of the second side wall, and a protruded portion formed in the portion on the inner wall side other than the portion on which the recessed portion is formed. The optical component is disposed between the protruded portions of the pair of second side walls, and is fixed with an adhesive filled in the recessed portions of the second side walls.
It is preferable that the mounting portion is a die pad of a lead frame, and that the first side walls, the second side walls, the optical component placement portion and the frame member are integrally formed with resin.
It is preferable that the protruded portions of the second side walls are inclined to an outer wall side, and an outer wall of a side face of the optical component is inclined to an inner side.
It is preferable that the height of the second side walls is higher than that of first side walls, and outer walls of the second side walls are arc-shaped, and inclined to the inner wall side.
It is preferable that a side wall recessed portion is provided in the first side wall in a vicinity of a portion where the second side wall and the first side wall meets.
It is preferable that the recessed portion of the second side wall and the side wall recessed portion of the first side wall are provided substantially along one direction.
It is preferable that the first side wall is longer than a length of a longer side of the optical component, and extends up to the recessed portion of the second side wall.
It is preferable that the optical component is higher than the second side wall, and a width of the optical component is smaller than that of the second side wall.
It is preferable that the adhesive is an ultraviolet curable adhesive.
A method for producing an optoelectronic apparatus of the present invention includes (a) preparing a member including a mounting portion for an optoelectronic device to be mounted on; (b) forming a frame member surrounding a periphery of the mounting portion and comprising an optical component placement portion positioned in an inner peripheral portion on a side of the mounting portion of the upper surface of the frame member, a pair of first side walls opposed to each other in a portion of an outer peripheral portion positioned on an outer side than the inner peripheral portion, and a pair of second side walls opposed to each other in the portion of the outer peripheral portion other than the portion on which the pair of first side walls are provided, a recessed portion formed on an inner wall side of the second side wall, and a protruded portion formed in the portion on the inner wall side other than the portion on which the recessed portion is formed, (c) mounting an optoelectronic device on the mounting portion; (d) placing the optical component on the optical component placement portion of the frame member; and (e) supplying an adhesive to the recessed portion with a nozzle for supplying an adhesive, thereby fixing the optical component to the optical component placement portion.
In one embodiment, in the process (a), a lead frame including a plurality of die pads are prepared as the member including a mounting portion for an optoelectronic device to be mounted on, and the process (b) includes setting the lead frame in a mold provided with an ejector pin; molding the frame member in the mold with resin; and removing the frame member from the mold by pressing the protruded portion of the frame member with the ejector pin.
In one embodiment, in the process (e), the nozzle is scanned above the recessed portion and along the recessed portion.
It is preferable that the process (d) includes semi-fixing the optical component with an ultraviolet curable adhesive and then performing optical alignment of the optical component and the optoelectronic device.
It is preferable that the process (e) includes supplying an ultraviolet curable adhesive as the adhesive to the recessed portion, and then curing the ultraviolet curable adhesive for secure fixation.
Another optoelectronic apparatus of the present invention includes an optoelectronic device, a mounting portion for the optoelectronic device to be mounted on, a frame member surrounding a periphery of the mounting portion, and an optical component. The optical component is placed on an optical component placement portion positioned in an inner peripheral portion on the side of the mounting portion of an upper surface of the frame member. The frame member comprises a side wall provided in an outer peripheral portion positioned on an outer periphery side than the inner peripheral portion of the upper surface of the frame member. An inclined portion is provided in a lower portion of the side wall of the optical component.
It is preferable that the inclined portion of the optical component is provided in a position lower than the upper surface of the side wall.
In one embodiment, an adhesive is filled between the side wall and the inclined portion, thereby fixing the optical component.
Another method for producing an optoelectronic apparatus of the present invention includes (a) preparing a member including a mounting portion for an optoelectronic device to be mounted on; (b) forming a frame member surrounding a periphery of the mounting portion and comprising an optical component placement portion positioned in an inner peripheral portion on a side of the mounting portion of the upper surface of the frame member, a side wall provided in an outer peripheral portion positioned on an outer side than the inner peripheral portion, (c) mounting an optoelectronic device on the mounting portion; (d) placing the optical component provided with an inclined portion at least in a lower portion of the side wall of the optical component on the optical component placement portion; and (e) supplying an adhesive to a space between the inclined portion of the optical component and the side wall of the frame member with a nozzle for supplying an adhesive, thereby fixing the optical component. The process (e) is performed by supplying the adhesive to a part of the inclined portion of the optical component, and allowing the adhesive to flow into a periphery of an lower region of the optical component.
In one embodiment, the process (e) comprises conveying the nozzle along one direction of the side wall of the frame member to supply the adhesive.
In the optoelectronic apparatus of the present invention, the recessed portions are formed on the inner wall side of a pair of second side walls. Thus, the recessed portions make the space between the optical component and the second side walls wide. As a result, the nozzle for supplying an adhesive can be inserted therein easily. Furthermore, the incident that the adhesive is applied to undesired portions of the optical component or the like can be reduced, and air bubble inside can be removed easily. Moreover, the optical component is disposed between the protruded portions of the pair of second side walls, and therefore alignment of the optical component can be performed in a simple and accurate manner. In addition, when the second side walls are used as the guide walls, optical alignment of the optoelectronic apparatus and the optical disk apparatus can be performed easily. Furthermore, in another optoelectronic apparatus of the present invention, an inclined portion is provided in at least a lower portion of the side wall of the optical component, so that the space between the optoelectronic component and the side wall can be made wide by the inclined portion. Therefore, the nozzle for supplying an adhesive can be inserted therein easily.
This and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.